Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds genuine non-obvious context: 'No account or prop_id needed' clarifies the auth/session requirement, and it names the pricing strategies returned (fast / balanced / max). It stops short of detailing latency, coverage limits, or failure modes for an open-world address lookup.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two tight paragraphs, front-loaded with the discovery-stage positioning, then the return contents, then routing. Every sentence carries distinct information with no repetition of the title or annotations.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a read-only two-parameter estimation tool with an output schema and safety annotations, the description covers stage, inputs needed, return shape, and sibling routing. Nothing an agent needs to call it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, and the schema already spells out the address format, ZIP requirement, and the unit-vs-embedded-unit preference in more detail than the description does. The description adds no parameter-level meaning beyond the incidental 'no prop_id needed' note, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource — estimate a property's SALE value — and names the two underlying sources (beycome CMA + Zillow Zestimate). It explicitly contrasts with the sibling rental tool and the comps tool, so an agent can distinguish it without opening any schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives explicit when-to-use ('Use during discovery to set a list price'), a pairing recommendation ('pair with beycome_comps'), and a named alternative for the adjacent case ('For rental inquiries, use beycome_rental_estimate instead'). Nothing is left to inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.